2, 3(alkyl mercapto) propyl esters of phosphinothioic and phosphonothioic acids



United States Patent 3,194,828 2,3(ALKYL MERCAPTQWROPYL ESTERS OF PHOS- PHINUTHIUIC AND PHOSPHUNOTHIGIC ACIDS Gerhard Schrader, Wnppertal-Cronenberg, Walter Lorenz,

Wuppcrtal-Vohwinkel, and Hans-Gerri Schicke, Wuppertal-Elberfeld, Germany, assignors to Farbenfabriken Bayer Aktiengesellschaft, Leverkusen, Germany, a German corporation N0 Drawing. Filed Aug. 16, 1960, Ser. No. 49,323

Claims priority, application Germany, Aug. 21, 1959,

F 29,219; Sept. 5, 1959, In 29,32ii 13 Qiaims. (Cl. 26l46l) The present invention relates to and has as its objects new and useful insecticidal thin-phosphoric, -phosphonic or phosphinic acid esters and processes for their production. Generally the new compounds of the present invention may be represented by the following formula:

In this formula R and R stand for lower alkylradicals, R and R stand for lower alkoxy groups or lower alkyl groups and X and Y stand for oxygen or sulfur, the lower alkyl and lower alkoXy having in each case up to 4 carbon atoms.

Certain alkyl-mercapto-alkyl esters of phosphoric acids are already known to be very active insecticides or generally pesticides. There is however need for compounds in this field which are efiicient against special pests or insects which in the meantime become resistant against attack of other insecticidal thiophosphoric acid esters.

It has now been found that the compounds of the above shown formula, which represent such a class of highly active compounds, may be prepared in various ways known in principle. Thus, if thiono-esters or thionothiol-esters are wanted corresponding suitably substituted 2,3-dimercapto propanols or mcrcaptanes are reacted with suitable thio-phosphoric, phosphonic or -phosphinic acid halides as it may be seen from the following equation:

If thiol-esters should be prepared either corresponding phosphoric, phosphonic or phosphinic acid halides may be reacted with suitably substituted 2,3-dimercapto propyl mercaptanes or suitable salts of thio-phosphoric, -phosphonic or -phosphinic acids may be reacted with suitably substituted 2,3-dimercapto to propyl halides. This reaction may be shown by the following formulae:

R1SCH CH-CH -SH at a P-Hal "2 O R: R:

Dithio compounds also may be obtained by reacting salts of suitable dithio-phosphoric, phosphonic or -phosphinic acids with suitable substituted 2,3-dimercapto- Patented July 13, led? propylhalides. This reaction may be shown by the following equation:

8 RiSOHg(l3ECI-I Ha1 ll SR2 P-SMe In the above equations the symbols R R R and R have the same significance :as given in the first formula.

The new compounds of the present invention very effectively kill insects like flies, mites, aphids, etc. They distinguish themselves especially by a good contact-insecticidal activity and at the same time by an activity on eating insects such as caterpillars. They may be used in the same manner as other known phosphoric insecticides, i.e. in a concentration from about 0.00001% to about 1%, diluted or extended with suitable solid or liquid carriers or diluents. Examples of such solid carriers are talc, chalk, bentonite, clay and the like, as liquid carriers there may be mentioned, water (if necessary with commercial emulsifiers), alcohols, especially lower alcohols such as methanol or ethanol, ketones, especially lower ketones such as acetone or methyl ethyl ketone, liquid hydrocarbons and the like. The new compounds may furthermore be used in combination with each other or with known insecticides, fertilizers etc.

As examples for the special utility of the inventive compounds the esters of the following formulae (I) CH3 0 C HsO S 2 6 SCHa OO H have been tested against spider mites and aphids. Aqueous solutions of the aformentioned' compounds have been prepared by admixing them with the same amount of an auxiliary solvent (acetone). A commercial emulsifier (benzyl hydroxy diphenyl polyglycol ether) is added in an amount of 20% referred to active ingredient. This premiXtu-re then is diluted with water to the desired concentration.

The tests have been carried out in the following manner:

(A) Against spider mites: bean plants (Phaseolus vulgarz's) of about 15 inches height are sprayed drip wet with solutions prepared as indicated above and in a concentration as shown below. The bean plants have been infested heavily with the two-spotted spider (species Tetranychus telarius). Evaluation has been carried out after 24 hours, 48 hours and 8 days. The following re,- sults have been obtained:

Aqueous concentration (in Killing rate Compound percent active (in percent) ingredient] water) (I) 0. O (II) 0. 01 100 (B) Against aphids of the type Doralis fabae: heavily infested bean plants (Vicia faba) have been sprayed drip wet with solutions as prepared above in a concentration as shown below. The efiect has been determined after 24 hours by counting the dead pests either on the surface is 67% of Th.

'3 of the soil or still remaining on the plants; The following results have been obtained:

Aqueous concentration (in Killing'rate Compound percent active. (in percent) ingre dient/ water) At 7080 C. there is added While stirring a solution of 1000 grams 2,3-dibromo-propanol in 500 ml. benzene. The mixture is kept for 2 hours at 80 C., then cooled to room temperature and stirred for further hours.

i The reaction product is washed with water, then :dryed over unhydrous sodium-sulfate and the solvent is distilled off. There are obtained 550 grams of the 2,3-thioethyl ether of n-propano=l as a colourless slightly waterso-luble liquid, boiling at 10 mm. Hg at 126-127 C. -The yield 270 grams pulverized nnhydrous potassium ,rnethylercaptide are suspended in 1300 ml. dry benzene and at 70-80 C. there are added while stirring 327 grams 2,3

dibromo-propanol dissolved in 250 ml. dry benzene.

Heating is continued for two hours at the same tempera- With an excess of thionyl-ch'loride the corresponding 2,3-dimethyl imercapto-l-chloropropane 47 grams ammonium salt of 0,0- -diethyl-thiol.phosphoric acid are dissolved in 150ml. acetonitril. At 70 C. there are added while stirring 50 grams 2,3-et'hyln1ercaptol-chloropropane (B-P- 12 mm./ 118 CA). Heating is continued for one hour to said above mentioned temperature. Then the reaction mixture is cooled and poured into 300 ml. icewater. The reaction product is taken 'up with 200 ml. benzene, Washed thoroughly with water and then dried over unhydrous sodium sulfate'. \Atter' f-ractionating there are obtained 46 grams of the new ester distilling at 0.01 mm./ 114 C. Yield 56% of the Th.

The ester is a colourless oil in water hardly soluble. It kills spider mites at 0.01 percent concentration (ovicidal lflClLlOIl) and aphids at 0.01 percent concentration (system. action 0.1%).

56 grams ammonium salt of diethyl-thionothiolphosphoric acid are dissolved in '150 ml. acetonitrile; At

.there are added while stirring 50 grams 2,3-ethylmercaptol-chloropropane. The mixture is kept for one hour at :7 5 C. and then worked up as described in Example No. 3. There are obtained 62 grams of the new ester distilling at 0.01 mm./1l3". C. Yield 71% of the Th. The ester is a colourless waterunsoluble oil. The ester shows a medium toxicity on rats per os (LD 50) of 5 mg/kg. It kills spider mites at a concentration of 0.001% (ovicidal action) and aphids at 0.01% (syst..action 0.1%).

43 grams ammonium salt of O-ethyl ethyl-thiol-phosphonic acid are dissolved in ml. acctonitrile. At 70- 75 C. there are added while stirring 2,3-ethylmercaptol chloropropane. The mixture is kept at 7580 C. for one 'hour'and then worked up as described in Example No. 3. In this rnannerthere are'obtained 49 grams of the new ester distilling at 0.01 mm./ C. Yield 62% of the Th. The ester is a colourless waterunsoluble oil and kills spider mites at a concentration of 0.001% (ovicidal action) and aphids at 0.001% (systemaction 0.1%).

I 7 Example 6 1 \ll P-S-OH CH-rOH -SCzH 2 50 S Cals 40 grams ammonium salt of O-ethyl methyl-thio-phosphonic acid are dissolved in 100 ml. acetonitrile. At 75 C. there'are added while stirring 50: grams 2,3-ethylrnercapto-l-chloropropane. The mixture is kept at 75-80 C. for one hour and then worked up as described in Example No. 3. In this manner'there are obtained 48 grams of the new ester distilling at 0.01 rum/108 Yield 64% of the Th. The ester is a colourless waterunsoluole oil and kills spider mites at a concentration of 0.001% (ovicidal action) and aphids at 0.001%. (system. action 0.1%).

Example 7 I CH3 S Example 8 \ll /P S-CH5-OI-I -CH;-SC H 021150 SO2H5 v V 52 grams potassium salt of O-ethyl ethyl-dithio-phosphonic acid are dissolved in mlgacetonitrile. At'75" there are added while stirring 50 grams 2,3-ethylmercapto l-chloropropane. The mixture is kept at 75 C. for one hour and then worked up in the usual manner.- There are obtained 50 grams of thenew ester distilling at 0.01 mm./

5 110. Yield 61% of the Th. The ester is a colourless waterunsoluble oil. Medium toxicity (LD 50/rat per s mg./kg. The ester kills spider mites at a concentration of 0.001% (ovicidal action) and aphids at 0.001%. (system. action 0.1%).

Example 9 PSOHg- CHCH;S CH3 C H O S0113 47 grams salt of diethyl-thiolphosphoric acid are dissolved in 200 ml. acetonitrile. While stirring there are added 43 grams 2,3-methylmercapto-1 chloropropane. (B.P. 7 mm./102 C.) The mixture is kept at 75 C. for two hours and then worked up as described in Example No. 3. In this manner there are obtained 48 grams of the new ester as a colourless waterunsoluble oil. Even in high vacuum the ester is only distillable under decomposition. It kills spider mites at a concentration of 0.01% (ovicidal action) and aphids at 0.001% (system. action 0.1%).

By exactly the same way there may be obtained the following compounds:

H C Hr-S C Ha 01330 S CH3 Example 10 CzHsO S CH3 51 grams ammonium salt of diethyl-thionothiol-phosphoric acid are dissolved in 200 ml. acetonitrile. At 75 C. 43 grams 2,3-methylmercapto-1-chloropropane are added while stirring. For two hours the mixture is kept at 80 C. and then worked up as described in Example No. 3. In this manner 59 grams of the new compound are obtained as a colourless waterunsoluble oil. Yield 74% of the Th. The ester kills spider mites at a concentration of 0.01% (ovicidal action) and aphids at 0.01%. (system. action 0.1%). Ihe ester is not distilll able, even in high vacuum.

Example 11 CZHB S \ll /PSGH -CHCH;SGH; CzHsO $0113 52 grams potassium salt of O-ethyl ethyl-thiono-thiolphosphonic acid are dissolved in 150 ml. acetonitrile. At 75 there are added While stirring 43 grams 2,3- methylmercapto-l chloropropane. The mixture is kept at 75-80 C. for a further hour and then worked up in the usual way. There are obtained 52 grams of the new compound distilling at 0.01 mm./ 112 as a waterunsolub-le colour less oil. Yield 69% of the Th. The ester kills spider mites at a concentration of 0.001% (ovicidal action). Aphids are killed at a concentration of 0.001% and caterpillars at 0.1%.

Example 12 IS OCgHa SCHa OC3H 46 grams mol) of 2,3-bis-methylmercaptoapropanol (B.P. 120 C./ 11 mm. Hg) are dissolved in 26 grams of anhydrous pyridine. 57 grams /1 mol) of diethyl-thionophosphoric acid monochloride are added dropwise while stirring at 40 C. The mixture is heated at C. for a further two hours and then stirred at room temperature for 5-6 hours. The reaction product becomes fairly consistent by the separated hydrochloric acid pyridine. 300 ml. of benzene are stir-red into the material which is washed several times with 100 ml. of ice water and then dried over sodium sulphate. After distilling off the solvent, 70 g. of the new ester are obtained as .a pale yellow oil which is distillable only with decomposition even in a vacuum and not soluble in water. Yield: 76% of the theoritical.

On rats per es the new ester shows a toxicity of 10 rug/kg. The ester kills aphids and spider mites at a concentration of 0.01% (ovicidal action). (System. action 0.1%.)

54 g. of 2,3 b-is-ethylmencapto-propanol BlP. 126 C./ 1O mm. Hg) are dissolved in 26 g. of pyridine. 57 g. mol) of diethyl-thionophosphoric acid chloride are added while stirring at 35-40 C. The mixture is heated at 40 for a further 2 hours and then after-stirred at room temperature for 1-2 hours. The precipitated hydrochloric acid pyridine renders the reaction product highly viscous. 300 ml. of benzene are stirred into the product which is washed three times with 100 rnL-portions of ice-water, dried over sodium sulphate, and the solvent is removed under vacuum. 53 g. of the new ester are thus obtained as a yellow water-insoluble oil which is not distillable without decomposition even under a high vacuum. Yield: 54% of the theoretical.

Toxicity on rats per os: 10 mg./kg. Aphids are completely killed at a concentration of 0.01% and they are killed at a concentration of 0.001% action) (system. action 0.1%

90 g. (0.5 mol) of 2,3-bis-ethylmercapto-propanol are dissolved in a sodium methylate solution containing /2 mol of dissolved sodium. Benzene is added and the methyl alcohol and benzene are distilled off azeotropically. The residual sodium salt is taken up with 500 ml. of methyl ethyl ketone: 80 g. of methyl-thionophosphonic acid-O-ethyl ester chloride (BP. C./ 12 mm. Hg) are added dropwise while stirring at 5060 C. The reaction product is kept at 60 C. for 2 hours and then taken up with 50 ml. of benzene. The benzenic solution is washed several times with 100 ml. portions of water. The benzenic solution is then dried and fractionated in vacuum. g. of the new ester of 13.1. 102 C./0.0l mm. Hg are thus obtained. Yield: 52% of the theoretical. Flies are killed at a concentration of 0.001%, aphids at 0.01%, spider mites at 0.01% and caterpillars at 0.1% (system.

( ovicidal 90 g. (0.5 mol) of 2,3-bis-ethylmercapto-propanol are dissolved in a sodium ethylate solution containing /2 mol of dissolved sodium. The ethyl alcohol and benzene are distilled off azcotropically with the addition of benzene.

The resulting sodium salt is taken up with 500 ml. of methyl ethyl ketone. 65 g. of dimethyl-thiono-phospninic acid chloride (13.1. 46 C./ 1 mm. Hg) are added drop wise while stirring at 60 C. The mixture is heated at 50-55 C. for 2 hours and then worked up in conventional manner. 45 g. of the new ester are thus obtained as a colourless oil which distils over at 92 C. under a pressure of 0.01 mm. Hg. Yield: 42% of the theoretical. We claim:

1. A compound of the formula wherein R and R individually stand for lower alkyl having up to 4 carbon atoms, R stands for a member selected from the group consisting of lower alkyl having up to 4 carbon atoms and lower alkoxy having up to 4 carbon atoms, R stands for lower alkyl having up to 4 carbon atoms and X and Y stand for a chalkogen of an atomic weight less than 40, at least one of them being sulfur.

2. The compound of claim 1 wherein X is oxygen, Y is sulfur and R .is lower alkoxy.

. 3. The compound of claim 1 wherein X and Y are sulfur and R is lower alkyl.

4-. The compound of claim 1 wherein X is sulfur, is oxygen and R is lower alkyl.

5. The compound of claim ll wherein X andY are sulfur and R is lower alkoxy.

6. The compound of claim 1 wherein X is sulfur,'Y is oxygen and R is lower alkoxy.

7. The compound of the following formula 21150 S CgHg,

g V 8. The compound of the following formula e p 1 's-on2 -onon2-son15 f z so SCrHa 9. The compound of the following formula on; s \ll P---S CHzC|HCHg-SC H CH: S Q2135 1.0. The compound of the following formula I C2115 S r f v PSCH2 (IJHCI'IZSCZH5 021E 50211 11. The compound of the following formula P-scH,oH-orn-sc1n CZH5O SQHs 12. The compound of. the following formula s out ll/ C H5S GH CH-OH OP I SOgH5 005115 13. The compound of the'following formula S OH;

|| o2n.s-on,on-orn-o1 SCzHs' 7 CH3 References Cited by theExarniner UNITED STATESPATENTS 2,777,792 1/57 'Lutz et al. 260- -461 2,864,741 12/58 Diveley 260- 461 2,944,933 7/60 Sallmann 260-461 2,956,074 10/60 Dorken et a1 260-461 2,959,516 11/60 Sallirn'ann 260-461 CHARLES B. PARKER, Primary Examiner. 

1. A COMPOUND OF THE FORMULA 